User:HusileBai/sandbox

North American Dipole (NAD) is a prominent mode of atmospheric dipole pattern over the North American sector, which largely impacts continental-scale ecological patterns and processes including bird irruption and conifer seed masting in the boreal forest. NAD is defined as the second principal component of summertime (June-August) mean 500-hPa geopotential height and is linked to tropical and monsoonal convective activities.